System and method for automated platelet wash

ABSTRACT

A method for washing platelets includes introducing anticoagulant into a platelet product container, drawing re-anticoagulated platelet product from the platelet product container, and introducing it into a centrifuge bowl. The centrifuge bowl separates the platelets from the supernatant in which they are suspended. The method then washes the platelets by introducing wash solution into the centrifuge bowl. As the wash solution is introduced into the bowl, it displaces the supernatant from the bowl and into a waste container. The method then introduces platelet additive solution into the centrifuge bowl, which displaces the wash solution from the centrifuge bowl and into the waste container and further wash the platelets. The method then repeatedly accelerates and decelerates the centrifuge bowl to resuspend the platelets in the platelet additive solution.

PRIORITY

This patent application claims priority from U.S. Provisional PatentApplication Ser. No. 61/410,738, filed Nov. 5, 2010, entitled, “Systemand Method For Automated Platelet Wash,” assigned attorney docket number1611/A68, and naming Etienne Pagès, Dominique Uhlmann, and MatthewMurphy as inventors, the disclosure of which is incorporated herein, inits entirety, by reference.

TECHNICAL FIELD

1. Technical Field

The present invention relates to systems and methods for washingcollected platelets, and more particularly to system and methods forwashing collected platelets in an automated and closed process.

2. Background Art

Apheresis is a procedure in which individual blood components (e.g.,platelets) can be separated and collected from whole blood temporarilywithdrawn from a subject. Additionally, blood components such asplatelets may be collected using a variety of other process. Oncecollected, these components may be stored and later transfused intopatients. However, in some instances, the receiving patient may haveadverse reactions (sometime severe) to the transfusion. For example, theoccurrence of adverse reactions such as allergic reactions, anaphylacticreactions, and/or febrile nonhemolytic transfusion reactions (FNHTRs) toplatelet concentrates (PCs) and/or platelet rich plasma (PRP) iswell-documented. A large number of these adverse reactions are caused bythe patients' sensitivity to the proteins contained within the plasma(e.g., the supernatant in which the platelets are suspended).Additionally, the plasma/supernatant may also contain a number ofcontaminates that are in solution with and/or suspended within thesupernatant. These contaminates may increase the severity of thereactions and/or may cause additional reactions.

In order to reduce the occurrence of these reactions, various prior artsystems “wash” the platelets to remove the plasma supernatant from theplatelet concentrate and/or PRP prior to transfusion. For example, priorart systems may dilute the platelet product with saline solution withinthe platelet collection bag. Once diluted, prior art systems and methodsthen centrifuge the diluted platelet product in order to form a“platelet pellet” at the bottom of the bag. The pellet supernatant(e.g., the plasma) may then be removed, for example, using a whole bloodseparation press, and the platelets resuspended in a different solution.The dilution procedure must then be repeated multiple times (e.g., atleast three times) in order to sufficiently remove the supernatant(e.g., the plasma) and proteins/contaminates. Once the supernatant andproteins have been sufficiently removed, the platelets may then beresuspended within a platelet additive solution. By essentiallyreplacing the plasma supernatant with platelet additive solution, priorart methods are able to reduce the risk of adverse reaction.

However, prior art systems and methods like those described above areproblematic for a variety of reasons. First, because prior art systemsrequire multiple sterile docking steps (e.g., in order to repeat thewashing procedure and to add the platelet additive solution), theproduct is not processed in a functionally closed manner which, in turn,increases the risk of contamination and reduces the length of time thatthe platelets can be stored. Additionally, manual processes inherentlyhave a high risk of human error and the results may vary depending onthe operator (e.g., they are not reproducible). Furthermore, the manualprior art procedures are labor intensive.

Summary Of The Embodiments

In accordance with one embodiment of the present invention, a method forwashing platelets includes introducing anticoagulant into a plateletproduct container, and drawing anticoagulated platelet product from thecontainer. The platelet product (e.g., platelet rich plasma) within thecontainer may contain platelets suspended within a supernatant (e.g.,plasma). The method may then introduce the anticoagulated plateletproduct into a centrifuge bowl which, in turn, separates the plateletsfrom the supernatant. Once the platelets are separated from thesupernatant, the method may then introduce wash solution (e.g.,anticoagulated saline glucose solution) into the centrifuge bowl todisplace the supernatant from the bowl (e.g., into a waste container),and introduce platelet additive solution into the centrifuge bowl todisplace the wash solution from the centrifuge bowl (e.g., into thewaste container).

After introducing the platelet additive solution and displacing the washsolution, the method may then “jog” the bowl by accelerating (e.g., fortwo second) and decelerating the centrifuge bowl (in the same directionor alternating between clockwise and counter-clockwise directions)multiple times (e.g., starting and stopping once and then repeating, forexample, three times) to resuspend the platelets in the plateletadditive solution. The method may then transfer the resuspendedplatelets and platelet additive solution to a platelet storagecontainer.

In additional embodiments, the method may transfer a portion of theresuspended platelets and platelet additive solution from the centrifugebowl to a platelet storage container and then, once again, repeat theaccelerating and decelerating process at least once (e.g., fouradditional times). After repeating the accelerating and deceleratingprocess, the method may then transfer the platelets and plateletadditive solution remaining within the centrifuge bowl to the plateletstorage container. The method may also add platelet additive solution tothe washed-platelet storage container after the system transfers theremaining platelets and platelet additive solution to thewashed-platelet container to achieve a predetermined washed-plateletvolume and/or a predetermined washed-platelet yield.

In some embodiments, the method may introduce anticoagulant into thewash solution prior to introducing the wash solution into the centrifugebowl. The method may also rinse the centrifuge bowl with plateletadditive solution after the second jogging step, and transfer theplatelet additive solution in the centrifuge bowl (e.g., the solutionused for the rinse) to the platelet storage container.

In accordance with additional embodiments, the method may agitate theplatelet product container (e.g., with a shaker) as anticoagulant is inintroduced into the platelet product container. Additionally, the methodmay also transfer a portion of the resuspended platelets and plateletadditive solution to the platelet storage container prior to initiallyjogging the centrifuge bowl.

In accordance with further embodiments of the present invention, asystem for automated platelet washing may include (1) a sterileconnection for connecting a platelet product container to the system andwithdrawing platelet product from the container, (2) a centrifuge bowl,(3) a wash solution source, (4) a platelet additive solution source, and(5) a controller. The centrifuge bowl separates the platelet productinto platelets and a supernatant, and may be configured to send thesupernatant to a waste container. The wash solution source may befluidly connected to the centrifuge bowl and configured to send washsolution to the centrifuge bowl. The platelet additive solution sourcemay be fluidly connected to the centrifuge bowl and configured to sendplatelet additive solution to the centrifuge bowl. The controllercontrols the operation of the centrifuge bowl, and may accelerate (e.g.,for two seconds) and decelerate the centrifuge bowl multiple times(e.g., four times) to resuspend the platelets within the plateletadditive solution (e.g., after the platelet additive solution is addedto the platelets and the supernatant is sent to the waste container).Accelerating and decelerating may include starting and stopping thebowl. In some embodiments, the controller may alternate starting thebowl in clockwise and counter-clockwise directions when accelerating anddecelerating the centrifuge bowl.

The system may also include a washed-platelet storage container, and thesystem may transfer a portion of the resuspended platelets to thewashed-platelet storage container after the controller accelerates anddecelerates (e.g., starts and stops) the centrifuge bowl. In suchembodiments, the controller may repeat the accelerating and deceleratingof the centrifuge bowl after the portion of the resuspended platelets istransferred to the washed-platelet storage container. Additionally, thesystem may transfer the remaining platelets and platelet additivesolution to the washed-platelet storage container after the controllerrepeats the accelerating and decelerating. The system may also includean anticoagulant source, and the system may introduce anticoagulant fromthe anticoagulant source into the platelet product container. In someembodiments, the controller may also be configured to add plateletadditive solution to the washed-platelet storage container after thesystem transfers the remaining platelets and platelet additive solutionto the washed-platelet container to achieve a predeterminedwashed-platelet volume and/or a predetermined washed-platelet yield.

In accordance with additional embodiments, a system for washingplatelets may include (1) means for introducing anticoagulant into aplatelet product container, (2) means for drawing anticoagulatedplatelet product from the platelet product container, (3) a centrifugebowl, (4) means for introducing wash solution into the centrifuge bowl,(5) means for introducing platelet additive solution into the centrifugebowl, and (6) a controller for controlling the operation of thecentrifuge bowl. The platelet product may contain platelets suspendedwithin a supernatant, and the centrifuge bowl may separate the plateletsfrom the supernatant. As it enters the bowl, the wash solution maydisplace the supernatant from the bowl and into a waste container.Similarly, as the platelet additive solution enters the bowl, theplatelet additive solution may displace the wash solution from thecentrifuge bowl and into the waste container.

The controller may accelerate and decelerate the centrifuge bowlmultiple times to resuspend the platelets within the platelet additivesolution after the platelet additive solution has displaced thesupernatant (e.g., contaminated supernatant) to the waste container. Thesystem may also include means for transferring the resuspended plateletsand platelet additive solution to a platelet storage container.

Some embodiments may also include means for transferring a portion ofthe resuspended platelets and platelet additive solution from thecentrifuge bowl to a platelet storage container. In such embodiments,the controller may also be configured to repeat the accelerating anddecelerating (e.g., stopping and starting) of the centrifuge bowl afterthe portion of the resuspended platelets is transferred to the plateletstorage container. The system may also include means for transferringthe remaining resuspended platelets and platelet additive solution fromcentrifuge bowl to the platelet storage container, and means forintroducing anticoagulant into the wash solution prior to introducingthe wash solution into the centrifuge bowl.

The controller may be further configured to alternate starting the bowlin clockwise and counter-clockwise directions when starting and stoppingthe centrifuge bowl. Additionally, the system may also include a shakerto agitate the platelet product container as anticoagulant is inintroduced into the platelet product container. In some embodiments, thecontroller may also be configured to add platelet additive solution tothe washed-platelet storage container after the system transfers theremaining platelets and platelet additive solution to thewashed-platelet container to achieve a predetermined washed-plateletvolume and/or a predetermined washed-platelet yield.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing features of embodiments will be more readily understood byreference to the following detailed description, taken with reference tothe accompanying drawings, in which:

FIG. 1 is a schematic diagram of a platelet wash system, in accordancewith one embodiment of the invention;

FIG. 2 is a schematic diagram of a disposable system for use with thesystem of FIG. 1, in accordance with one embodiment of the presentinvention.

FIG. 3A schematically shows a side view of a centrifuge bowl for usewith the platelet wash system of FIG. 1, in accordance with someembodiments of the present invention.

FIG. 3B schematically shows a side view of an alternative centrifugebowl for use with the platelet wash system of FIG. 1, in accordance withsome embodiments of the present invention.

FIG. 3 c schematically shows a side view of a third centrifuge bowl foruse with the platelet wash system of FIG. 1, in accordance with someembodiments of the present invention.

FIG. 4 is a flow chart depicting a method for washing collectedplatelets and platelet product, in accordance with one embodiment of thepresent invention; and

FIG. 5 is a flow chart depicting an alternative method for washingcollected platelets and platelet product, in accordance with additionalembodiments of the present invention.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

Referring to. FIGS. 1 and 2, an automated platelet wash system 100 usesa centrifuge 110, such as the centrifuge bowl described within U.S. Pat.No. 4,983,158, which is hereby incorporated by reference, to separateplatelets from its supernatant (e.g., the fluid in which the plateletsare suspended). Other types of separation chambers and devices may beused, such as, without limitation, a standard Latham type centrifuge(FIG. 3C), as described in U.S. Pat. Nos. 3,145,713 and 5,882,289, whichare hereby incorporated by reference.

The centrifuge 110 includes a rotating bowl 120 and stationary input andoutput ports PT1 and PT2 that are typically closely coupled to the bowlinterior by a rotary seal 74 (see FIG. 3A). Although the material andsize of the bowl 120 may vary depending upon the application and amountof platelet product to be washed, preferred embodiments of the presentinvention utilize bowls having volumes ranging from 210 to 275 ml andmade from K-resin. Additionally, the system 100 may be a blood/cellprocessing system such as the ACP® 215 system by Haemonetics, Corp.and/or the red blood cell cryopreservation and recovery apparatusdescribed in U.S. Pat. No. 6,440,372, which is hereby incorporated byreference.

As shown in FIG. 3B, in some embodiments, the centrifuge bowl 120 mayinclude a core 121 with a diverter 122 located within the interior ofthe bowl 120, such as the centrifuge bowl described within U.S. Pat. No.4,943,273, which is hereby incorporated by reference. The diverter 122may be a donut-like member located near the bottom of the bowl 120 andmay have openings 123 at the peripheral edge and openings 126 betweenthe openings 123 and the core 121. As fluid to be processed (e.g.,platelet product, PRP, etc.) enters the bowl 120 through input port PT1,the fluid flows through feed tube 124 and into the bottom of the bowl120. The centrifugal forces then force the platelet product to flowoutwardly and upwardly through openings 123 and into separation region125. As wash solution (or platelet additive solution) enters the bowl120, the wash solution may enter separation region 125 though openings126 to create a washing cross-flow.

The input port PT1 of the centrifuge bowl 120 is in fluid communicationwith a platelet product container 130 via a tube 132, connector 134,tube 136, and a Y-connector 138. Tubes 132 and 136 have compatibilitywith blood and blood products, as is all the tubing in the system 100.The platelet product container 130 may contain platelet product (e.g.,platelet rich plasma) derived from a donor using a blood apheresissystem such as the MCS apheresis systems available from Haemonetics,Corp. As described in greater detail below, the inlet port PT1 is alsofluidly connected to a variety of solution containers 140/150/160(described in greater detail below) via valves V1/V2/V3, tubes144/154/164, connector 112, and tube 115. The outlet port PT2 of thecentrifuge bowl 120 is fluidly connected to a waste container 170 by atube 116, a valve V4 and a tube 118.

As mentioned above, in addition to the platelet product container 130,the inlet port PT1 of the centrifuge 110 may also be fluidly connectedto a number of solution containers 140/150/160. The solution containersmay include a bag or container 140 for storing anticoagulant, a washsolution storage container 150, and a platelet additive solution storagecontainer 160. The use of each of these solutions is described ingreater detail below. The tube 115 connecting the solution containers140/150/160 to the centrifuge bowl 120 may include a bacteria filter 180that prevents any bacteria within the anticoagulant, platelet additivesolution, and/or wash solution from entering the system 100. Containers140/150/160 are preferably plastic bags made of material that iscompatible with the solution that each bag contains.

The system 100 may also include a controller 190 that controls theoverall operation of the system 100 and the centrifuge 110. For example,the controller 190 may control the operation of peristaltic pumps P1and. P2, as well as, valves V1/V2/V3/V4 to control the direction andduration of flow through the system 100. Additionally, the controller190 may also control the operation of additional system components suchas a shaker 192 and printer 194 (if equipped). The printer 194 may beused to print reports and/or other information regarding the process. Asdiscussed in greater detail below, the shaker 192 may be used during there-anticoagulation of the platelet product contained within container130. The controller 190 may also be coupled to a display screen 196 thatpresents information to a system operator, and an input device 198 thatallows the system operator to input information and supply thecontroller 190 with information. For example, the input device 198 mayallow the user to input a desired final platelet volume (e.g., a volumegreater than the bowl 120 volume) and/or a desired final platelet yield.As discussed in greater detail below, the controller 190 may addplatelet additive solution to the washed-platelet product in order toachieve the desired volume and/or yield.

It is important to note that, in other embodiments of the presentinvention, the shaker 192 and the printer 194 may be stand alonecomponents that are not connected to the system 100. In suchembodiments, these components may operate independently from the system100 and controller 190. For example, the shaker 192 may be anindependent device with its own operational controls (e.g., it may notbe controlled by controller 190).

In order to monitor the pressure within the system 100, the system mayalso include one or more pressure sensors. For example, the system 100may include a pressure sensor 122 on tube 136 to measure the pressurebetween the pump P1 and the washed platelet collection bag 175.Similarly, the system 100 may also include a pressure sensor 126 on tube118 to measure the pressure between the centrifuge bowl 120 and thewaste container 170. Each of the pressure sensors 122/126 may include afilter 124/128 (e.g., a 0.2 μm hydrophobic filter and/or anti-bacterialfilter) to preserve sterility within the system 100.

As shown in FIG. 2, various components may be packaged together as adisposable set 200. For example, the disposable set 200 may includetubes 115/116/118/132/144/154/172/174, connectors 134/138/112, valvesV1/V2/V3/V4, the centrifuge bowl 120, the bacteria filter 180, the wastecontainer 170, and the washed platelet storage container 175.Additionally, the disposable set 200 may also include connection portsfor the solution containers 140/150/160, and the platelet productcontainer 130. For example, the disposable set 200 may include a firststerile connection 131 for connecting the platelet product container130, a second sterile connection 162 for connecting the plateletadditive solution container 160, and connections 142/152 (e.g., spikeconnections, luer-lock connections, etc.) for connecting the washsolution container 150 and the anticoagulant container 140. Prior tostarting the platelet wash procedure, the disposable set 200 may beremoved from its packaging and installed into the system 100, as shownin FIG. 1.

FIG. 4 is a flowchart depicting a method for washing platelet product,in accordance with one embodiment of the invention. First, the systemoperator may connect the platelet product container 130 to the sterileport 131 (step 401) and connect the anticoagulant container 140, washsolution container 150, and platelet additive solution container 160 toconnectors 142/152/162 (step 402). Once the containers are connected,the system 100 may add anticoagulant (e.g., to re-anticoagulate) to theplatelet product within the platelet product container 130 (Step 403).To that end, the system 100 may energize pumps P1 and P2 and use thepumps P1/P2 (e.g., in series) to draw anticoagulant from container 140through tubes 144 and 115, bacteria filter 180, lines 136, and 132 andinto the platelet product container 130. In order to aid mixing of theplatelet product and the anticoagulant, the platelet product container130 may be placed on shaker 192 which agitates the solutions (e.g., theplatelet product and the anticoagulant) within the platelet productcontainer 130.

Once the anticoagulant is added to the platelet product, the system 100may transfer a volume (e.g., all or part) of the re-anticoagulatedplatelet product to the centrifuge bowl 120 (Step 404) and begin tocentrifuge the re-anticoagulated platelet product (step 405). Althoughthe rate at which the platelet product is transferred to the centrifugebowl 120 and the speed at which the bowl 120 is rotated (e.g., tocentrifuge the platelet product) may vary, some embodiments of thepresent invention may transfer the platelet product at 150 ml/min androtate the centrifuge bowl 120 at approximately 8000 RPM. As theplatelet product enters the bowl 120 (e.g., separation region 125), thecentrifugal forces on the platelet product will begin to separate theplatelets from the supernatant (e.g., plasma) and cause the platelets tomigrate towards the outer diameter of the bowl 120.

The system 100 may then continue to rotate the bowl 120 and begin towash the platelets with wash solution (e.g., saline glucose) (Step 406).During this step, the pump P2 will begin to draw wash solution fromcontainer 150 and wash the platelets contained within the bowl 120 byintroducing the wash solution into the centrifuge bowl 120 through inletport PT1 . As the wash solution enters the centrifuge bowl 120, the washsolution will begin to mix with the supernatant (e.g., there-anticoagulated plasma) within the bowl 120 and separated from theplatelets. As additional wash solution enters the bowl, the washsolution/plasma mixture will be displaced from the centrifuge bowl 120through the outlet port PT2 and will be sent to the waste container 170through tubes 116 and 118. Although the rate at which the system 100introduces the wash solution to wash the platelets may also varydepending on the application and/or volume of platelet product beingwashed, some embodiments of the present invention wash the platelets at150 ml/min for a total of 1500 ml of wash solution. Additionally, it isimportant to note that, during the wash step, the centrifuge 110 andbowl 120 continue to rotate at approximately 8000 RPM and the washsolution is continuously displaced (e.g., out port PT2 and into wastecontainer 170) as additional wash solution is introduced into the bowl120.

In some embodiments, it may be beneficial to add anticoagulant to thewash solution (e.g., a ratio of 1:20) prior to transferring the washsolution to the centrifuge bowl 120. To that end, the system100/controller 190 may add anticoagulant to the wash solution atconnector 112 and/or as it flows through line 115. For example, as pumpP2 is drawing the wash solution from container 150, the controller 190or system operator (if the valves are manual valves) may open and closevalve V1 at appropriate intervals to meter anticoagulant into lines 144and 115 as the wash solution is being transferred to the bowl 120.

It is important to note that, by adding anticoagulant to the plateletproduct and the wash solution, the pH of the platelets and contents ofthe bowl 120 temporarily decrease (e.g., while the platelets are beingwashed with the wash solution). This temporary decrease in pH helpsprevent the platelets from adhering to each other during processing.Additionally, as discussed in greater detail below, the pH of the finalplatelet product (e.g., the washed platelets) increases (e.g., to above6.4) once the platelets are resuspended in the platelet additivesolution.

After the system 100 performs the initial wash step (e.g., Step 406)with wash solution, the system 100 will then begin the final plateletwash (Step 407). During the final platelet wash, the system 100 willclose valve V2 and open V3 in order to transfer the platelet additivesolution from container 160 to the centrifuge bowl 120. As the plateletadditive solution is transferred to the centrifuge bowl 120, theplatelet additive solution will mix with the wash solution remainingwithin the bowl from the initial wash step (e.g., Step 406).Additionally, in a manner similar to the initial wash step with the washsolution (e.g., Step 406), the system 100 will transfer a greater volumeof platelet additive solution than the centrifuge bowl 120 can hold. Forexample, the final wash step may transfer 500 ml of platelet additivesolution at 150 ml/min while the bowl 120 is rotating at approximately8000 RPM. However, as platelet additive solution enters the bowl 120through the inlet port PT1, an equivalent volume of the plateletadditive solution/wash solution mixture will be displaced through outletPT2 and flow into the waste container 170. Once the final wash step iscomplete, the system 100/controller 190 may stop the centrifuge.

After completing the final wash (Step 407) and stopping the centrifuge110 and bowl 120, the system 100/controller 190 may agitate and/or jogthe bowl 120 (Step 408 to help remove any platelets that may be stuck tothe side of the centrifuge bowl 120 by commencing a series ofacceleration and deceleration steps prior to emptying the bowl 120. Forexample, the controller 190 may start/accelerate the centrifuge 110/bowl120 for a predetermined amount of time (e.g., 2 seconds) and thendecelerate the centrifuge 110/bowl 120. The jogging (e.g., thealternating acceleration and deceleration) creates turbulence within thebowl 120 and induces movement of the fluid in the bowl 120 relative tothe bowl 120 which, in turn, helps remove the platelets from the wall ofthe bowl 120. The system 100/controller 190 may repeat thisacceleration/deceleration process multiple time (e.g., 3 additionaltimes).

It is important to note that, in some embodiments, the controller 190does not need to stop the bowl between the acceleration and decelerationsteps. For example, the controller 190 does not need to allow the bowl120 come to a complete stop during the deceleration step beforeaccelerating the bowl 120. Additionally, to decelerate the bowl 120, thecontroller may simply de-energize the bowl 120/centrifuge 110 and allowthe bowl 120 to decelerate on its own (e.g., by the friction within themotor, bowl 120, etc.). In other words, in some embodiments, thecontroller 120 does not have to actively brake the bowl 120 duringdeceleration.

In some embodiments, the acceleration and deceleration steps may includestarting and stopping the bowl 120. For example, the initialacceleration step may start the bowl 120 from a stop. In suchembodiments, the controller 190 may also bring the bowl 120 to acomplete stop (or allow the bowl 120 to come to a complete stop) duringthe deceleration step.

Once the initial agitation step is complete (Step 408), the system10D/controller 190 may partially empty the bowl 120 (Step 409) by usingpump P1 to remove a volume of the platelet additive solution andplatelets from the bowl 120, and transfer the volume to the washedplatelet storage container 175. By reducing the volume within thecentrifuge bowl 120, the “sloshing” and turbulence within the bowl 120is increased during subsequent agitation steps, discussed below.

The system 100/controller 190 may then begin a second jogging/agitationstep (Step 410) in which the system 100/controller 190 repeats theagitation process (Step 408). For example, the system 100/controller 190may, once again, accelerate and decelerate (e.g., starts and stops) thebowl 120 multiple times in order create turbulence within the bowl 120and remove the platelets from the walls of the bowl 120. Additionally,like the first agitation step (Step 408), the controller may acceleratethe bowl for predetermined period of time (e.g., 2 seconds) anddecelerate the bowl 12 repeatedly (e.g., four times total).

The direction of rotation of the centrifuge 110 and bowl 120 may dependupon the type of system 100 and centrifuge 110 used. For example, ifequipped with a dual-direction centrifuge, the system 100/controller 190may alternate the direction of rotation for each acceleration/startcycle. In other words, the system 100/controller 190 may alternaterotating the bowl 120 in clock-wise and counter-clock-wise directions(e.g., in order to increase the turbulence within the bowl 120).Additionally, although the agitation steps arc described above asaccelerating/starting the centrifuge 110 for two seconds and repeatingthree times (e.g., for a total of four start/stop cycles), the time andnumber of repeats can vary. For example, some embodiments of theinvention may accelerate/start the centrifuge for three seconds andother embodiments may start the centrifuge 110 for one or four or moreseconds. Likewise, some embodiments may only repeat theacceleration/deceleration steps twice and other embodiments may repeatfour or more times.

Once the second jogging/agitation step (Step 410) is complete, thesystem 100/controller 190 may stop the centrifuge 110 and empty the bowl120 (Step 411). For example, the controller 190 may energize pump P2 anddraw the remaining platelets and platelet additive solution through theinlet port PT1 and transfer the platelets/platelet additive solution tothe washed platelet storage container 175.

As mentioned above, the addition of anticoagulant to the plateletproduct and wash solution reduces the pH of the platelets and plateletproduct during washing. However, once the platelet additive solutiondisplaces the wash solution within the bowl 120 and the platelets areresuspended in the platelet additive solution, the pH increases to alevel more suitable for platelet storage (e.g., above 6.4 and/or the pHof the platelet additive solution).

In addition to the steps described above and shown in FIG. 4, someembodiments may also include additional, optional steps. For example, asshown in FIG. 5, prior to starting the initial jogging/agitation step(Step 408), some embodiments may stop the centrifuge 110 and transfer asmall volume (e.g., 50 ml) of platelet additive solution and plateletsfrom the bowl 120 to the washed platelet storage container 175 (Step501). By doing so, the system 100 may improve the “sloshing” andturbulence within the bowl 120 which, in turn, helps remove theplatelets from the walls of the centrifuge bowl 120.

Additionally or alternatively, some embodiments may conduct a finalrinse step (Step 502) after emptying the bowl 120 (e.g., after Step411). During the final rinse step, the system 100/controller 190 maytransfer a volume (e.g., 35 ml) of platelet additive solution to thecentrifuge bowl 120. The system 100/controller 190 may then accelerateand decelerate (e.g., start and stop) the bowl 120 in a manner similarto steps 408 and 410 to rinse out any remaining platelets contained withbowl 120. This rinse may then be transferred to the washed plateletstorage container 175.

Furthermore, if the operator input a desired platelet volume or desiredplatelet yield into the input device 198 (discussed above), thecontroller 190 may add platelet additive solution to the washed-plateletproduct within collection bag 175 to obtain the programmed volume oryield (Step 503). For example, the controller 190 may use pumps P1 andP2 (e.g., in series) to transfer the required volume of plateletadditive solution from container 160 to the collection container 175.

It is also important to note that the flow rates and volumes discussedabove are only meant as examples, and the flow rates and volumes mayvary. For example, the wash solution flow rate and volume may be greaterthan or less than 150 ml/min and 1500 ml, respectively. Additionally,the platelet additive solution flow rate and volume may be greater thanor less than 150 ml/min and 500 ml, respectively. Furthermore, the RPMprovided above is similarly meant only as an example and may vary. Forexample, the RPM may be less than or greater than 8000 RPM (e.g., it maybe between 7000 and 7500 RPM, less than 7000 RPM, or greater than 8000RPM).

The systems and methods described above provide numerous advantages overthe prior art. In particular, because embodiments of the presentinvention are conducted within a closed system, there is a reduced riskof contamination and the final product (e.g., the washed platelets) canbe stored for greater periods of time. For example, platelets washedwith embodiments of the present invention may be stored for greater than24, as compared to only 6-8 hours for platelets washed with the priorart manual procedures described above.

Additionally, because various embodiments of the present invention areautomated, the results (e.g., platelet recovery, protein removal, etc.)are reproducible and less subject to operator error. For example,embodiments of the present invention are repeatedly able to reduce theprotein within the platelet product by greater than 80% (and up to 99%)and repeatedly recover greater than 80% of the platelets within theinitial platelet product (e.g., the PRP).

The embodiments of the invention described above are intended to bemerely exemplary; numerous variations and modifications will be apparentto those skilled in the art. All such variations and modifications areintended to be within the scope of-the present invention as defined inany appended claims.

What is claimed is:
 1. A method for washing platelets comprising: (a)introducing anticoagulant into a platelet product container containingplatelet product, the platelet product containing platelets suspendedwithin a supernatant; (b) drawing anticoagulated platelet product fromthe platelet product container; (c) introducing the anticoagulatedplatelet product into a centrifuge bowl and centrifuging theanticoagulated platelet product to separate the platelets from thesupernatant; (d) introducing a wash solution into the centrifuge bowl,the wash solution displacing the supernatant from the bowl into a wastecontainer; (e) introducing platelet additive solution into thecentrifuge bowl, the platelet additive solution displacing the washsolution from the centrifuge bowl into the waste container; (f) joggingthe centrifuge bowl by accelerating and decelerating the centrifugebowl; (g) repeating step (f) at least once to resuspend the platelets inthe platelet additive solution.
 2. A method according to claim 1 furthercomprising transferring the resuspended platelets and platelet additivesolution to a washed-platelet storage container.
 3. A method accordingto claim 1, wherein step (f) is repeated four times.
 4. A methodaccording to claim 1, further comprising: (h) transferring a portion ofthe resuspended platelets and platelet additive solution from thecentrifuge bowl to a washed-platelet storage container; (i) repeatingstep (f) at least once; and (j) transferring the platelets and plateletadditive solution remaining within the centrifuge bowl to thewashed-platelet storage container.
 5. A method according to claim 4,wherein step (i) includes repeating step (f) four times.
 6. A methodaccording to claim 4, further comprising: rinsing the centrifuge bowlwith platelet additive solution after step (j); and transferring theplatelet additive solution in the centrifuge bowl to the plateletstorage container.
 7. A method according to claim 4, whereinaccelerating the centrifuge bowl includes starting the centrifuge bowlfrom a stop and decelerating the centrifuge bowl includes stopping thecentrifuge bowl.
 8. A method according to claim 7, wherein acceleratingthe centrifuge bowl includes starting the centrifuge bowl in alternatingdirections.
 9. A method according to claim 4, further comprising addingplatelet additive solution to washed-platelet storage container afterstep (j) to achieve a predetermined washed-platelet volume.
 10. A methodaccording to claim 1, wherein the wash solution is saline glucosesolution.
 11. A method according to claim 1, further comprisingintroducing anticoagulant into the wash solution prior to introducingthe wash solution into the centrifuge bowl.
 12. A method according toclaim 1, further comprising agitating the platelet product container asanticoagulant is in introduced into the platelet product container. 13.A method according to claim 1, wherein the platelet product is plateletrich plasma and the supernatant is plasma.
 14. A method according toclaim 1, wherein the centrifuge bowl is accelerated for two secondsprior to decelerating during step (f).
 15. A method according to claim1, further comprising transferring a portion of the resuspendedplatelets and platelet additive solution prior to step (f).